import java.util.concurrent.Semaphore;

/**
 * Created with IntelliJ IDEA.
 * Description:
 */
public class Demo4 {
    public static int count=0;

    public static void main(String[] args) {
        Semaphore semaphore=new Semaphore(1);
        Thread t1=new Thread(()->{
            for(int i=0;i<5000;i++) {
                try {
                    semaphore.acquire();
                    count++;
                    semaphore.release();
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        });
        Thread t2=new Thread(()->{
            for(int i=0;i<5000;i++) {
                try {
                    semaphore.acquire();
                    count++;
                    semaphore.release();
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        });
        t1.start();
        t2.start();
        try {
            t1.join();
            t2.join();
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        System.out.println(count);
    }
}
